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Freshly printed Midori stickers just arrived, in November the last ones of the old batch were being given out to visitors of the OpenRheinRuhr. So I ordered new ones at FlyerAlarm, a print company based in Würzburg, Austria. This time around I went for circular ones and slightler smaller than they used to be. This size also fits better on phones and tablets for those who like to decorate theirs with stickers. You might also notice that the colors are better and the graphic comes out better – fixes to the SVG will be finding their way into the repository soon.

With the new stickers I’m well-prepared for Chemnitz Linux Days this march, in a little more than a fortnight. There will be a Midori booth there. Be sure to add the weekend of March 19 and 20 to your calendars!

As things go we diverged a bit from the original plan of making a big compatibility break with this release. Instead much of the original branch has been broken off into pieces that made their way into trunk. We did however bump WebKit2, libSoup and Zeitgeist dependencies. The most visible change is support for CSD, client side decorations, also called header bars after the API in GTK+3.10 (enabled via GTK_CSD=1). With no further adue here goes Midori 0.5.11 with a whole lot of nice things and a ton of bug fixes! Peek at the change log if you want more details.

We are excited and proud of announcing WebKitGTK+ 2.8.0, your favorite web rendering engine, now faster, even more stable and with a bunch of new features and improvements.

Gestures

Touch support is one the most important features missing since WebKitGTK+ 2.0.0. Thanks to the GTK+ gestures API, it’s now more pleasant to use a WebKitWebView in a touch screen. For now only the basic gestures are implemented: pan (for scrolling by dragging from any point of the WebView), tap (handling clicks with the finger) and zoom (for zooming in/out with two fingers). We plan to add more touch enhancements like kinetic scrolling, overshot feedback animation, text selections, long press, etc. in future versions.

HTML5 Notifications

Notifications are transparently supported by WebKitGTK+ now, using libnotify by default. The default implementation can be overridden by applications to use their own notifications system, or simply to disable notifications.

WebView background color

There’s new API now to set the base background color of a WebKitWebView. The given color is used to fill the web view before the actual contents are rendered. This will not have any visible effect if the web page contents set a background color, of course. If the web view parent window has a RGBA visual, we can even have transparent colors.

A new WebKitSnapshotOptions flag has also been added to be able to take web view snapshots over a transparent surface, instead of filling the surface with the default background color (opaque white).

User script messages

The communication between the UI process and the Web Extensions is something that we have always left to the users, so that everybody can use their own IPC mechanism. Epiphany and most of the apps use D-Bus for this, and it works perfectly. However, D-Bus is often too much for simple cases where there are only a few messages sent from the Web Extension to the UI process. User script messages make these cases a lot easier to implement and can be used from JavaScript code or using the GObject DOM bindings.

Sending a message from the web process to the UI process using JavaScript is very easy:

window.webkit.messageHandlers.foo.postMessage("bar");

That will send the message “bar” to the registered foo script message handler. It’s not limited to strings, we can pass any JavaScript value to postMessage() that can be serialized. There’s also a convenient API to send script messages in the GObject DOM bindings API:

Who is playing audio?

WebKitWebView has now a boolean read-only property is-playing-adio that is set to TRUE when the web view is playing audio (even if it’s a video) and to FALSE when the audio is stopped. Browsers can use this to provide visual feedback about which tab is playing audio, Epiphany already does that

HTML5 color input

Color input element is now supported by default, so instead of rendering a text field to manually input the color as hexadecimal color code, WebKit now renders a color button that when clicked shows a GTK color chooser dialog. As usual, the public API allows to override the default implementation, to use your own color chooser. MiniBrowser uses a popover, for example.

APNG

APNG (Animated PNG) is a PNG extension that allows to create animated PNGs, similar to GIF but much better, supporting 24 bit images and transparencies. Since 2.8 WebKitGTK+ can render APNG files. You can check how it works with the mozilla demos.

SSL

The POODLE vulnerability fix introduced compatibility problems with some websites when establishing the SSL connection. Those problems were actually server side issues, that were incorrectly banning SSL 3.0 record packet versions, but that could be worked around in WebKitGTK+.

WebKitGTK+ already provided a WebKitWebView signal to notify about TLS errors when loading, but only for the connection of the main resource in the main frame. However, it’s still possible that subresources fail due to TLS errors, when using a connection different to the main resource one. WebKitGTK+ 2.8 gained WebKitWebResource::failed-with-tls-errors signal to be notified when a subresource load failed because of invalid certificate.

Ciphersuites based on RC4 are now disallowed when performing TLS negotiation, because it is no longer considered secure.

Performance: bmalloc and concurrent JIT

bmalloc is a new memory allocator added to WebKit to replace TCMalloc. Apple had already used it in the Mac and iOS ports for some time with very good results, but it needed some tweaks to work on Linux. WebKitGTK+ 2.8 now also uses bmalloc which drastically improved the overall performance.

Concurrent JIT was not enabled in GTK (and EFL) port for no apparent reason. Enabling it had also an amazing impact in the performance.

Seven months of sweat and tears… oh well, not quite so dramatic. In any event Midori 0.5.9 is out!

We’re already scheming… I mean planning for the next cycle. We want to go WebKit2 and GTK+3 only now and do away with the fourfold compatibility setup. Anyone who finds this thrilling is more than welcome to join in; the fun is going to start soon.

At OpenRheinRuhr 2014 we had a Midori booth again. Almost didn’t happen due to the strike of Deutsche Bahn which caused many people to miss the event. Fortunately my humble self made it.

In addition to stickers, this time around we even had edible gummi paws!

Amongst the most posed questions was process isolation, something WebKit2 provides, and which will be available to everyone soon once our plan to move fully towards GTK+3, WebKit2 and Vala is put in motion. The other one was why Midori crashed so often – which is due to the at least 4 primary build configurations currently available. I’m very much looking forward to seeing this go away at some point in the future.

Pretty happy with the results personally, was able to get a decent number of people curious to try out Midori and in one instance even install it on site.

After six months of development, the latest version of Xubuntu has been released! Xubuntu 14.10 “Utopic Unicorn” features the latest in Xfce development and is the first step towards the next Long Term Support release in 2016.

Here’s 10 new things to look for in the latest release. For a more comprehensive list of changes and a list of download links, please see the official release announcement and release notes.

Appearance Updates

The login screen received a minor visual refresh and greater customization options.
LightDM GTK+ Greeter with the latest Greybird theme.

The new wallpaper for this release adds a splash of pink to the Xfce mouse.
The new default wallpaper for Xubuntu 14.10 “Utopic Unicorn”

To celebrate the 14.10 codename “Utopic Unicorn”, pink highlights have been added. These highlights can be reverted or easily changed to another color with the installed “Theme Configuration” utility.
Using “Theme Configuration”, you can easily change Xubuntu’s colors to match your mood.

With the latest Xfce Display Settings, managing multiple monitors is no longer a hassle. Just drag and rearrange the displays to your liking.
The new drag-and-drop display settings greatly improves multihead support.

With the updated Xfce window manager, the Alt-Tab switcher has been updated with a refreshed appearance and the ability to select windows with your mouse or by touch.
Even minor features like the Alt-Tab switcher have been improved.

With the latest Whisker Menu and changes to the default configuration, applications in the Settings Manager are now searchable.
Quickly find and launch any application with the Whisker Menu.

Application Updates

With Catfish 1.2, previewing files has been greatly simplified. Easily switch between details and preview mode. When the search index becomes outdated, Catfish will also notify you to update.
Catfish makes searching for images easier with the latest release.

Parole 0.7 introduces a new Clutter-based backend and finally supports video playback in Virtualbox. The media controls are now contained in a slide-over overlay (with a configurable timeout).
Parole’s interface is further refined with each new release.

Light Locker Settings has been improved, further integrating with Xfce Power Manager to handle screensaver settings.
Light Locker Settings can now integrate with other screensaver managers.

That’s it for this release, now to get ready for 15.04 “Vivid Vervet”!

The answer is simple, Midori needs a Debian package maintainer! Thousands of Debian and Ubuntu users are facing the above situation, including lots of Raspberry Pi users. A single person stepping up to it can literally change the world at this point. Now if fame isn’t motivation enough, there may be a t-shirt to get.

GTK+ 3 plugins in WebKitGTK+

The WebKit2 GTK+ API has always been GTK+ 3 only, but WebKitGTK+ still had a hard dependency on GTK+ 2 because of the plugin process. Some popular browser plugins like flash or Java use GTK+ 2 unconditionally (and it seems they are not going to be ported to GTK+ 3, at least not in the short term). These plugins stopped working in Epiphany when it switched to GTK+ 3 and started to work again when Epiphany moved to WebKit2.

To support GTK+ 2 plugins we had to build the plugin process with GTK+ 2, but also some parts of WebCore and WebKit2 (the ones depending on GTK+ and used by the plugin process) were built twice. As a result we had a WebKitPluginProcess binary of ~40MB, that was always used for all the plugins. This kind of made sense, since there were no plugins using GTK+ 3, and the GTK+ 2 dependency was harmless for plugins not using GTK+ at all. However, we realized we were making a rule for the exception, since most of the plugins don’t even use GTK+, and there weren’t plugins using GTK+ 3 because they were not supported by any browser (kind of chicken-egg problem).

Since WebKitGTK+ 2.5.1 we have two binaries for the plugin process: WebKitPluginProcess2 which is exactly the same 40MB binary using GTK+ 2 that we have always had, but that now is only used to load plugins using GTK+ 2; and WebKitPluginProcess, a 7,4K binary that is now used by default for everything except loading plugins that use GTK+ 2. And since it links to GTK+ 3, it might load plugins using GTK+ 3 as well. Another side effect is that now we can make GTK+ 2 optional, WebKitPluginProcess2 wouldn’t be built and only plugins using GTK+ 2 wouldn’t be supported.

At the WebKitGTK+ hackfest in 2012 we started to think about how to implement the integrated document reading in Epiphany based on the design mockups. We quickly discarded the idea of implementing it as a NPAPI plugin, because that would mean we had to use a very old evince version using GTK+ 2. We can’t implement it inside WebKit using libevince because it’s a GPL library, so the first approach was to implement it inside Epiphany using libevince. I wrote a first patch, it was mostly a proof of concept hack, that added a new view widget based on EvView to be used instead of a WebView when a document supported by evince was requested. This approach has a lot of limitations, since it only works when the main resource is a document, but not for documents embedded in a HTML page or an iframe, and a lot of integration problems that makes it quite difficult to maintain inside Epiphany. All of these issues would be solved by implementing it as a NPAPI plugin and it wouldn’t require any change in Epiphany. Now that WebKitGTK+ supports GTK+ 3 plugins, there’s no reason not to do so.

Thanks to a project in Igalia I’ve been able to work on it, and today I’ve landed an initial implementation of the browser plugin to Evince git master. It’s only a first implementation (written in C++ 11) with the basic features (page navigation, view modes, zoom and printing), and a very simple UI that needs to be updated to match the mockups. It can be disabled at compile time like all other frontends inside Evince (thumbnailer, previewer, nautilus properties page).

Another advantage of being a NPAPI plugin is that it’s scriptable so that you can control the viewer using JavaScript.

And you can pass initial parameters (like current page, zoom level, view mode, etc.) from the HTML tag.

WebKitGTK+ 2.5.1 is the first version of this release cycle. It comes very late mainly due to the regressions introduced by the switch to CMake and the problems we found after removing WebKit1 from the tree. It also includes some new features that I’ll talk about in other posts, probably when 2.6.0 is released. In this post I’ll only focus on the breaks introduced in this release, in order to help everybody to adapt their applications to the API changes if needed.

Wait, but why breaking the API?

Since the release of WebKitGTK+ 2.0 the WebKit1 API has been considered deprecated and in maintenance mode. The new WebKit2 API is quite complete and stable now, so the plan for WebKitGTK+ 2.6 was removing WebKit1, leaving it alive, but still in maintenance mode, in the 2.4 branch. After removing the code from trunk we realized that newer versions of WebKitGTK+ that are WebKit2 only should be parallel installable with older versions of WebKitGTK+ that also include WebKit1. After some discussions trying to find the best solution, we reached the conclusion that we had to bump the binary version. But then I thought, since we were going to force everybody to recompile, why not take advantage to introduce some small (but necessary) API changes that in most of the cases will not affect the the users anyway? And then I started to review the API and proposing some changes. I also wanted to make sure all API changes were introduced in the first unstable release, so that users only have to adapt their applications once, and that’s the main reason why the release has taken so long.

Binary version bump

The new binary version is 4.0, so to use this new release you need to update your build system to look for webkit2gtk-4.0 pkg-config file.

GObject DOM Bindings

The GObject DOM bindings API situation was actually the main reason for breaking the API. The problem was that the code for the DOM bindings is generated automatically from the IDL files. This means that every time a new IDL file was added to the build system, we ended up exposing a new class in our public API without even noticing. Same happened when a API incompatible change was introduced in an IDL file, for example to update it to the current standard. We added a script to our build bots to warn us when that happened, and then we had to manually deprecate the existing API and add exceptions to the code generator. This was a lot of work just to keep backwards compatibility of an API nobody was using. Most of the people actually use a 5-10% of the DOM bindings API.

Since WebKitGTK+ 2.5.1 the GObject DOM bindings API is split into stable and unstable parts. The stable part contains the most commonly used API that it’s unlikely to change. We will keep maintaining backwards compatibility of this part of the API. The rest of the API is considered unstable and might change at any time, you can still use it but at your own risk. We thought this solution was better than just removing the unstable API. There are two kind of unstable APIs:

Classes that are considered unstable: the entire class is considered unstable. The header is not included in the main webkitdom.h header, so to use them you have to include the header file explicitly.

Unstable symbols of stable classes: a method or constant in a stable class that is considered unstable. In this case the header file is included by the main webkitfom.h header, but it doesn’t contain any unstable symbols, they are included in a new header WebKitDOMClassNameUnstable.h that also needs to be included explicitly.

In both cases you need to define WEBKIT_DOM_USE_UNSTABLE_API before including the headers

WebKit2 GTK+ API

The API changes in the WebKit2 GTK+ API could have been avoided, by deprecating symbols and adding new ones, but since we were going to break the API anyway, and the affected symbols are not that commonly used we thought it was worth it.

WebKitWebView::create: the signal now receives a WebKitNavigationAction parameter containing information about the navigation action that triggered the event. So now you can know the type of event (if it was a link clicked, a form submitted, etc.), the mouse button and keyboard modifiers, the URI request or even if it was a user gesture. This information is very useful to implement a popup blocker, for example.

WebKitWebViewGroup has been removed. This class was only introduced to add the user stylesheets API, since most of the people actually use the default web view group. The grouping of pages inside WebKit2 is something that will be eventually removed, in favor of users doing the groups they need. The user stylesheets API has been moved to a new class WebKitUserContentManager that will also be extended to support user scripts. The settings can still be handled directly with the WebKitWebView API, so that if you want a group of web views to share the same settings you can simply call webkit_web_view_set_settings() for all the web views passing the same WebKitSettings object.

View mode API: The view source mode was removed from WebCore, and the API was already marked as deprecated. Since it’s very unlikely we add more view modes, we just removed the API. There’s no replacement for this, but it could be easily implemented either using a external window with a GtkSourceView or embedded into a WebKitWebView by using a custom URI scheme and a JavaScript library for syntax highlighting.

CMake

Since version 2.5.1 WebKitGTK+ uses CMake instead autotools as its build system. The equivalent to configure, make and make install now would be something like this: